1. Field of the Invention
The present invention relates to apparatus for movably supporting an object and, in particular, to apparatus for adjustably supporting an imbalanced object between two points which are not in complete alignment.
2. Description of the Prior Art
In a host of environments throughout modern society it has been proven expedient to support an object between two points. Frequently, it is advantageous to adjustably support an object by suspending it from two points which may be disposed on a frame in the form of a yoke. An example of an article employing such a general construction is a lamp which is pivotally supported by a yoke-type frame member. In particular, a surgical lamp used in various medical environments may employ such a configuration.
In such an application, it is desirable to allow the lamp to be pivotable, yet retainable in a modified position, within such a support to allow the directing of the light generated by the lamp to the required locale. One prior art apparatus for adjustably supporting an object between two points on a yoke included a pair of shafts attached between the yoke and the object. One of such shafts included a radial drum brake disposed about the end of the shaft, which end included a means for slightly increasing the shaft's diameter thereby causing it to be engaged by the drum brake. An inherent limitation in such a system was the fact that if the axis of rotation of the object was not exactly that of the shaft, the shaft would ride unevenly on the drum brake thereby causing binding or inadequate braking of the object in its supports.
Another prior art apparatus for adjustably supporting an object also included twin shafts affixed between a yoke and the object. One of the shafts was provided with a friction surface perpendicular to the shaft's axis. A parallel opposing friction surface was provided in facing relation to the shaft's friction surface such that the friction created between the friction surfaces would provide adjustability and subsequent retention of the object's position. Unfortunately, as will be readily appreciated, the surfaces were required to be retained absolutely parallel to avoid binding which necessitated the provision of a straight axis of rotation through the axis of the shaft.
As such, heretofore due to the requirement of a straight axis of rotation for the lamp within its support, the points of engagement of the lamp with its support were required to be in complete alignment. Otherwise, if the axis of rotation was skewed relative to the support points, free pivoting and, hence, the directing of light to the needed spot was not possible. Clearly, therefore, if a support member is to be constructed to allow adjustment of a light, the support points must have been in complete alignment. To accomplish such a construction, the manufacturing time, skill and equipment required, and hence, the resulting apparatus cost, was high. Further, the costs associated with increased assembly and adjustment times were significant.
Another concern of the prior art relating to adjustably supporting an object related to the balancing of the object. It has heretofore been the usual feeling that the object was required to be balanced to avoid its unwanted movement after positioning. It will be readily appreciated that such required balance of a surgical lamp interfered with the efficiency of the lamp design and added to the engineering costs as well as increasing the costs of its respective parts and its overall manufacture. Also, the prior art practice of simply adding counterweights to the lamp is clearly inefficient, cost-adding and often ineffective.
The subject invention is directed toward an improved support means for an article, such as a surgical lamp, to be supported between two points which overcomes, among others, the above-described shortcomings of the prior art and which is effective to adjustably support, yet positively position, a lamp means.